KCNE4 Background Information The KCNE genes encode small, single transmembrane domain peptides that associate with pore-forming å-subunits to form K+ channels with unique characteristics. Voltage-gated K+ channels in the plasma membrane control the repolarization and the frequency of action potentials in neurons, muscles, and other excitable cells. KCNE4 (K+ voltage-gated channel, Isk-related family, member 4), also known as minimum K+ ion channel-related peptide 3 (MiRP3), belongs to a family of proteins known to have a dramatic effect on the gating of certain potassium channels. KCNE4 is expressed strongly in heart, skeletal muscle, and kidney. Electrophysiological studies show that human KCNE4 inhibits the KCNQ1 channel. KCNE4 also plays a role in inhibiting the currents of Kv1.1 and Kv1.3. Alternatively, it is a key player in increasing the current amplitude of the KCNQ4 channel.
